Steps to Execute Constraints:
1. Navigate to the Electrical > Electrical Constraint Set > Routing > Wiring worksheet.
2. Scroll horizontally to the Max Parallel column, then in that same column, select the cell for any of the Electrical Constraint
sets shown below. Then a Parallel Segments window will appear.
3. Enter some values that would work for your design calculations (e.g. not allowing traces that are 0.1016 mm / 4 mils apart
to traverse more than 5.08 mm / 200 mils together). Click Ok.
4. With the constraint set values set, apply the constraint set by going to the Electrical > Net > Routing > Wiring worksheet.
5. Click one of the applicable nets (e.g. PCIE0_CLKREQ) then apply the constraint set (in this case NVEC1_1_PCIE0_CLK_)
Reason: Signal integrity constraints are crucial for maintaining data integrity, especially in high-speed designs where signals
are more susceptible to degradation and interference.
Impact on the Board:
f
Reduces signal distortion and data errors
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Improves overall system reliability and performance
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●May influence trace routing, layer stack-up, and component placement decisions
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Can lead to more complex design rules and potentially increased PCB manufacturing costs
By implementing proper signal integrity constraints, designers can ensure that their PCBs maintain signal quality and
minimize interference, resulting in more reliable and higher-performing electronic products.
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OrCAD X High-Speed Digital Design Guide
